The Chemicals of Sentiment
by Lorazzle
Summary: "I can see them too" Sherlock spoke after what felt like an eternity of comfortable silence. Molly raised her eyes to meet his, smiling shyly, she reached her hand out to stroke the Thestral's skeletal frame.


AUTHORS NOTE: Hey! It's my first Sherlolly. I've always wanted to do a crossover of Sherlock and Harry Potter, and thus, this thing was born. It' set in their last year at Hogwarts. It's quite smutty towards the end, but the beginning is..I guess a bit sad? Anyway, I hope you enjoy it and leave me a big nice review. If you want me to continue this please say, or I was thinking of making one-shots and you all could leave prompts in reviews.

Hope you enjoy!

CHAPTER 1: DEATHLY DEDUCTIONS

It had been two weeks since her Muggle father's passing and the ache in Molly Hooper's chest had not lessened. Her despair was laced with anger, she felt betrayed. What good was it to be able to control magic, bending it to her will, when she could not use it to save her own father? Cancer was an illness just as much an enigma to wizardry as it was in the Muggle world. It was by accident that Molly came across the skeletal horses while she was on a walk to clear her mind. Yet, she knew she had accepted her father's death because she was able to see these magnificent creatures. Having witnessed his last breaths, she now was able to gaze her eyes upon their leathery bat-like wings and their reptilian-like facial features.

Molly sat down in the cool grass, inhaling the crisp air. Rubbing at her eyes with the heel of her palm she let out a drawn out sigh, feeling older than her seventeen years. She had just managed to escape the feast that was happening in the Great Hall, she'd much rather be in the company of the Thestrals than the students of Hogwarts at the moment. Being shy and quiet had helped the Ravenclaw escape the constant overwhelming sympathy of her classmates; nobody noticed her grief because Molly Hooper simply did not count. The only person who seemed to have an inkling of suspicion that something had changed in the small girl's demeanor was Sherlock Holmes. Molly wasn't surprised, his skill of observation was impressive - he was able to tell which student was cheating on their OWLs based on the quill they picked that day. Sherlock had a clear grasp of character, and those steely blue eyes assessed Molly thoroughly this past week, unhinging her. She blushed heavily under his scrutinizing looks whenever she realised he was assessing her. The Slytherin's best friend, John Watson, a Gryffindor if you could believe it, who was always close by his side, told Molly that Sherlock had a 'Mind Palace' in which he used to categorize his thoughts. She sometimes found herself wondering if he had a room that he placed her in. Would it be simplistic, plain walls, basic furniture? Those were dangerous thoughts. They gave her false hope that he could have even a semblance of attraction to her as a person.

"Evening Dad," Molly whispered to herself, as she watched a young Thestral nuzzle its mother's leg, "I wish you were here. Mum has… well she has never understood me as well as you have. Soon, I'm taking my final exams, and then hopefully I'm off to training to be a Pathologist. I wonder what you'd call me. 'Morbid, Morgue Molly'! Um, something similar to that at least. I hope you are happy, wherever you are. I'm…I'm not happy Dad, sometimes I hate you for leaving me." Molly stifled a sob, placing a trembling hand in front of her mouth. There was no need to disturb the peaceful horses with her misery.  
"I can't do this on my own Dad, I love y-" Molly Hooper's words were cut off abruptly. The sound of a twig snapping echoed in the distance. Craning her neck in the direction of the noise, Molly searched for the source. Resigning it to just be a woodland creature, she left her speech unfinished. Instead, Molly watched the Thestrals, admiring the way they trotted and greeted each other. Tucking a stay hair behind her ear, Molly then rested her chin on her palm.

"Avoiding the feast?" Sherlock's rich baritone broke through her calamity. Molly could not help but let out a gasp, whipping her head around. She did not know where to focus her stare. At first she took in all his features, his high cheekbones, then his strong jaw and narrow nose, before finally meeting his eyes.  
"Yes. Um, uh, I, I… I don't seem to be in," Molly collected her thoughts, cursing Sherlock's ability to cause her pathetic stuttering, "the right…mood."

Sherlock raised one eyebrow, offering her a nod. He looked as if he wanted to turn away for a moment, but he thought better of it. He unclasped the expensive pin holding together his robes and placed it on the floor next to Molly. His next course of action was to proceed to sit down and Molly's heart rate elevated at seeing him in his shirt. What in Merlin was he doing? Sherlock looked forward; purposely avoiding Molly's confused expression and instead focused on the Thestrals that were now less than a metre away from them.

"I can see them too" Sherlock spoke after what felt like an eternity of comfortable silence. Molly raised her eyes to meet his, smiling shyly, she reached her hand out to stroke the Thestral's skeletal frame. The creature huffed, stretching its long neck towards Molly, wanting her to continue her ministrations. Molly complied; after all, they were kind enough to keep her company these past weeks. Molly was not sure what to respond, so she let Sherlock carry on.

"Death," Sherlock paused for a moment, pushing an unruly curl away from his eyes, "is a guarantee in life. It's an inevitability that we all must come to terms with. When I was younger, I solved my first murder case; unfortunately the client was poisoned. It was a pity really, his wife was not too happy about his affair and he collapsed right in front of me. Of course, I had no qualms accepting death before, but that was the first time I watched death play her card."

"What happened to the woman?" Molly asked curiously. Briefly aware that the Thestral had trotted away.

"She's was locked up, that part was Auror Grant. I merely pointed out that it was her motive to kill him all along, she was already embezzling his money, but she killed him because she still 'loved him' she claimed. How boring. What a trivial excuse. Sentiment? Sentiment is a chemical default found on the losing side."  
"Who's Grant?" Molly inquired.  
"Grant Lestrade. He is probably the only Auror in the Department of Magical Law Enforcement to make use of at least half of his intellect. Tragic really, that's where I come in; I assist him in cases since his whole team is incompetent."  
Molly bit her lip in deep consideration.  
"I've heard of him. Greg. He's been in the papers a few times."  
"Who's Greg?" Sherlock stared at Molly, questioningly.  
"Greg Lestrade? That's his actual name. You just spoke about him."

"Oh. Yes right, Greg, Grant, George," Sherlock waved his hand dismissively, "It's all the same thing to me. Do you know what I am good at Molly Hooper?"  
"Creeping up on girls in the woods?" Molly giggled at the exasperated look Sherlock sent in her direction. Molly turned her whole body to face Sherlock; she waited for him to continue. Sherlock mirrored her actions. Now the two students were face to face, and Molly was unnerved, waiting for Sherlock to make the next move. The Sherlockian steeple finally made itself known. Molly admired his long graceful musician fingers.

"I'm the Wizarding's and the Muggle's world's only consulting detective. I'm not going to go into detail about how I do what I do because chances are you wouldn't understand. I observe everything, from what I observe I deduce. When I have eliminated the impossible, whatever remains, no matter how improbable, must be the truth. Molly Hooper, you are showing all the signs of grieving. You denied the realisation of your father's death to your peers, instead telling them nothing was wrong. You care about what people think of you, how boringly mundane. Then, you became angry. Judging by the way these past few months you have speared your potatoes so hard you've chipped numerous plates – the House Elves aren't too please with that by the way. Then, you bargained the situation in an attempt to regain control." Molly stared wide-eyed as Sherlock carried on, he put on a despaired voice, "_If only I realised sooner! I should've spent more time with him!" _You have been overwhelmed with grief since his death, look at the state of your lips!"

Molly reacted by touching them, tracing the broken skin with her fingertips. She always had a bad habit of biting them whenever she was sad, gnawing at them in worry.

"Normally you opt to put on two coats of mascara every morning; recently, you haven't even put on one. Not caring about your appearance to your peers every morning as you've been overwhelmed by the thought of your late father. Finally, the old watch around your wrist. Far too large a strap for a woman's use, its leather is old, losing its quality from the amount of times it's been taken on and off someone's wrist. Conclusion: A Hooper family heirloom, belonging to your father. He clearly loved you back just as much, judging by the amount of letters you received from him, you always mouthed a phrase he signed off his letters with, 'Don't worry. Be happy.' He would not wish to see you in this state."

Molly felt her eyes welling up with tears, but pushed them back, she did _not_ want a repeat of last Christmas, where she cried in front of him, even if he was being nicer this time with his deductions. Sherlock had gotten everything so…so right.

"That's amazing. I mean, I am grieving, yes. My dad died, obviously…as you know. And I…I come here because the Thestrals. They understand what it's like to be associated with death and they are content to be here. People are scared of them, you know they are –"  
"Occupied with their ghastly appearance? Classified as XXXX on the Ministry Scale, and travel by them is considered as illegal, as it is a breach of the International Statue of Wizarding Secrecy." Sherlock's intellectual prowess interrupted, "At first they seem rather dull, don't they? They have the same anatomy as horses, just with wings. They are in fact, very smart. If trained correctly, they are able to understand their riders words when they are ask to travel to a specific location. I admire their ability of being able to discern a friend from an enemy. A Thestral tail hair is a substance that can only be mastered by a wizard or a witch who are capable of facing death. It can be used as a core in a wand." Sherlock stated as if he was reading from a textbook. Molly's eyes trailed to his cupid bow lips, distracted by the way they formed words.

If Sherlock noticed where she was looking, he did not comment. He merely grasped her hand and felt her pulse point, softly stroking the area of soft skin. Molly shuffled closer to Sherlock, they were knee-to-knee now and she felt emboldened by his words. For once, Molly Hooper was going to assert herself and control the situation. Leaning in towards him, she whispered in his ear, her breath causing him to shiver.

"I'm curious as to why you think sentiment is a chemical default. How long have you been _deducing_ me, detective?" He felt her smile against his ear, and his eyes widened. Molly Hooper had always counted to him, and he had - much to John's relentless teasing, observed her this past year, finding himself intrigued by the girl.

"For some time now," Sherlock grasped Molly's waist and pulled her into his lap, which shocked both of them, pressing his lips against her neck he carried on, "Sentiment is a chemical default because it makes me lose if I fall victim to it, I chose to not act upon it because it's simply base desires. But with you, I find myself wanting to explore this side of my nature."

Molly wriggled in his lap, as he began to suck on her pulse point, how did things escalate this quickly. Her mind was whirling with questions and thoughts which all ceased when Sherlock began to trail kisses down her collarbones. The forest's serene atmosphere was now filled with Molly's light panting as Sherlock carried on his assault with his tongue. She felt his hard desire pressed up against her sex as her skirt had rode up, and moved against it.

"Bloody hell" Molly gasped, "If someone told me I'd be dry humping Sherlock Holmes in a forest after I was grieving alone, I'd tell them to bugger off." Sherlock chuckled and paused in his actions, raising his head from her chest he placed a soft kiss to the corner of Molly's lips, and then swiftly captured her lips with his own. Molly moaned into his mouth, grasping hold of the rich, dark curls she had fantasies of looping round her fingers. She captured his lower lip between her pearly teeth, enjoying the groan Sherlock released.

"Shy Molly Hooper, what a wonderful façade you have crafted for yourself" Sherlock noted, his hands now cradling Molly's bum as she rocked against him.  
"Oh, it's painfully obvious I'm normally very shy, detective, but right now I'm fueled by desire. Now, how are you going to tackle this case?" Molly Hooper smiled devilishly and she grasped his want through his trousers.

Sherlock grunted and muttered something that sounded suspiciously like 'minx', pushing Molly to her back; he spread her legs around his waist and looked down at her. A huge smile graced his features and as he traced one long finger along the seam of her panties, he replied.

"Molly Hooper, I'm going to enjoy solving you."


End file.
